Aruba ARM! Its the greatest!
Recently I’ve been checking out a bunch of the Cracked “If so&so ads were honest” series. They are quite hysterical. Theme Parks, Grocery stores, Expensive purses….they all give a very interesting perspective on whats really going on and the thoughts that these industries/companies probably have behind closed doors.
Every time I have to mess with ARM, I think about these videos. I hear Mr. Horton saying:
“We know that setting channels statically is probably easier but we just don’t think you are intelligent enough to do it. So use ARM! Why mess with channels when you could be sitting on the beach with a Corona and reading Feci-Fi blogs on your new wireless network?!?”
Does seem kind of true though, doesn’t it? It can’t be that hard to add a command to the controller that says “put this radio on this channel and power and leave it there.” It’s easy with an IAP, why not with a controller?
At least in AOS8 it seems be available. Until then, here is what I did to get a full static channel configuration on my latest system.
Some RRM thoughts…
So are “ARM” type systems all stupid and useless? No, I believe that ARM has its place in the wireless world. In certain environments riddled with neighbors using RRM technology to adjust(or not adjust) all their channels. There has to be a way to tweak RRM to respond to their unknowledgeable high schooler “tech on the side” guy that threw up 40 Ruckus APs in a gas station and called it a network. Never mind the fact that they are all on 80Mhz channels, 10 foot apart, and using 36e and 149e. Hopefully AOS 8’s Airmatch will be better at determining these situations and react better.
However, I’ve learned throughout my life that its really best to have a good foundation. In housing, a bad foundation will cause your house to fall over. Currently, I’m getting quotes to repair my cinderblock wall in my basement. Its buckled an inch and a half inward and the previous homeowner’s paint just started to crack. Convenient. (This of course is after I put 15K into a full 2 bedroom apartment.) The right side of my house is skewed 2 inches -because of a bad foundation. In life, a bad foundation will lead you into years of trouble with yourself and others. Counseling, jail, lifelong unhappiness, who knows? But it will happen if your foundation isn’t solid.
Creating a static plan for your building ensures that your wireless has a good foundation. Its solid and will not change (excluding DFS). Then by utilizing spectrum analysis and WIDS and WIPS, you can be notified of events that are trying to cause problems to your network and then you can go deal with those events accordingly.
Aruba configuration is all based on profiles. VAP profiles, Radio Profiles, SSID profiles, etc. Its a great design because you can build all the profiles out in the beginning and then just point and click your way through new AP deployments as opposed to hand configuring every new AP and site that comes online.
The problem with this regarding static channels is that the channel and power settings are inside the 802.11a radio profile. This means that if you change the channel inside that profile, its going to change it for every AP that is associated with that profile. On top of that, the power settings (Transmit EIRP) are inside the advanced tab of that profile. What does that mean? It means you’ll need a radio profile for every channel, and every necessary power level of that channel. *note that there is an 802.11g radio profile for 2.4. I’ll stick to “a” profiles for this post but it applies to both.
The best way to do this is of course in the CLI. To get that configuration, I created a new radio profile in the GUI and then checked the CLI for the configuration. You’ll end up with something like this:
rf dot11a-radio-profile “profile_name”
For the naming convention, I decided on this:
This tells me (and future engineers) that the Channel(dash)power is 036-01. I padded with the 0 because Aruba orders everything numerically by the first digit. Regardless if it is 2 or 3 digits long. If you don’t pad with 0, you end up with this structure:
Very annoying to my obsessive compulsive side. It also makes the profile list a mess.
So now I have this:
rf dot11a-radio-profile “Ch-Tx_036-01”
To create all the other profiles, I popped that into excel and created a bunch of concatenate formulas to create a profile for every other combination that I needed. For the 26 5Ghz channels, I created a power setting for 1-10, 15, 20, 25, and 30. 14 Profiles per channel = 364 profiles!
And that’s not all!
Now that you have your 364 radio profiles, you then have to apply those profiles to each AP! So instead of having 364 lines of configuration that you should really need, now you have that plus however many APs:
One careful note about quotes: Aruba OS uses quotes, but does not like quotes being pasted in. Before you paste copied configuration back into any Aruba controller using AOS6, find and replace ALL quotes with nothing:
If you don’t, you’ll end up with configuration that looks like this:
rf dot11a-radio-profile ““Ch-Tx_036-01″
It will create new profiles in addition to the current ones and make your configuration very confusing. Also, NEVER use spaces. (This should be a given.)
I’ve read some of the Aruba Airheads responses to static channel requests and they always point to the “regulatory domain”. They say “remove all the channels you don’t want and then apply the domain to the AP”. In investigating this solution, I’ve found that while that will help with keeping the channels static, the power will still fluctuate depending on ARM. Maybe I’m wrong, but meh. There’s more than one way to skin a….potato.
So there it is! Can’t tell you how long I searched for something like this when I was a little Aruba certified associate. Unfortunately, knowledge like this isn’t getting me closer to ACMX. Back to studying!
’til next time!